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1.
目的:在单细胞水平上研究小鼠腹腔巨噬细胞(PM)基态游离钙离子浓度([Ca2+]i)的不均一性及其和细胞反应性的关系。方法:用荧光指示剂Fura-2/AM结合荧光显微镜成像系统检测单个PM基态的及用激动剂刺激细胞后的[Ca2+]i;同时结合NBT染色法定量检测单个PM产超氧阴离子(O2-)水平。结果:对7只正常小鼠共392个PM基态[Ca2+]i的研究表明小鼠PM的基态[Ca2+]i呈正态分布[(54±24)nmol/L,n=392],但波动范围较大(从10nmol/L到高于100nmol/L),以[Ca2+]i在40-60nmol/L的细胞数量最多(约占50%)。用PMA、fMLP刺激后PM[Ca2+]i升高,且受刺激后[Ca2+]i升高的峰值和基态[Ca2+]i之间呈正相关(PMA刺激组:r=052,P<0.01,n=58;fMLP刺激组:r=0.59,P<0.01,n=44。此两组实验均以不同的小鼠重复3次,其它两只小鼠的结果与上同。下面的表述方法同此)。另外小鼠PM的基态[Ca2+]i与其受PMA刺激后产生O2-的量也呈显著正相关(r=0.42,P<0.01,n=43,重复4次)。结论:小鼠PM的基态[Ca2+]i是不均一的,且基态[Ca2+]i的高低和该细胞对致炎因子的反应性密切相关。  相似文献   

2.
目的:研究脂蛋白(a)氧化前后致人动脉平滑肌细胞(SMC)增殖及细胞内游离钙浓度([Ca2+]i)的变化,观察阿魏酸钠(SF)对其的影响。方法:Lp(a)经体外Cu2+氧化法氧化,硫代巴比妥酸(TBARS)比色法检测氧化程度,培养的人动脉SMC中分别加入不同浓度SF,作用12h后再与天然和氧化型Lp(a)共同孵育,以MTT比色法、流式细胞仪检测细胞增殖状况,采用荧光探针Fura-2/AM检测细胞[Ca2+]i。结果:氧化型Lp(a)促人动脉SMC增殖的同时亦明显增加了[Ca2+]i水平,作用较天然Lp(a)明显,SF(40,80mg/L)可显著抑制氧化型Lp(a)所致的细胞增殖和[Ca2+]i增加,并呈剂量效应关系,而对天然Lp(a)所致的细胞增殖和[Ca2+]i增加无明显影响。结论:氧化型Lp(a)通过升高[Ca2+]i而显著促动脉SMC增殖可能是其致动脉粥样硬化的机制之一,SF拮抗这种作用可能与其抗氧化能力有关。  相似文献   

3.
目的:研究噻庚啶(Cyp)和山莨菪碱(Ani)对肿瘤坏死因子(TNFα)诱导单个内皮细胞内Ca2+浓度([Ca2+]i)变化的影响,以探TNFα介导休克和Cyp、Ani的抗休克的机制。方法:人脐静脉内皮细胞株(ECV304)接种于35 mm含2 mL DMEM培养基的组织培养盘中培养。Fluo-3/AM负载细胞,激光扫描共聚焦显微技术(LSCM)测定单个内皮细胞[Ca2+]i。结果:TNFα使单个内皮细胞[Ca2+]i呈剂量依赖性升高,在60 s内达到峰值,然后下降并保持在基础水平之上。共聚焦扫描图像显示细胞核区[Ca2+]i升高比胞浆区明显,下降比胞浆区慢。Cyp(3×10-5 mol/L或6×10-5 mol/L)、Ani(2×10-5 mol/L或4×10-5 mol/L)均能显著抑制由TNFα(1.2×10-9 mol/L)诱导的单个内皮细胞[Ca2+]i升高。结论:TNFα诱导内皮细胞[Ca2+]i升高可能是TNFα介导休克的重要机制;Cyp和Ani抑制TNFα诱导的[Ca2+]i升高可能是其抗休克作用的机制之一。  相似文献   

4.
内皮素-1对培养鼠肝星状细胞内游离钙的影响   总被引:2,自引:0,他引:2  
目的:观察内皮素-1(ET-1)对培养肝星状细胞(HSC)的胞内钙[Ca2+]i的影响。方法:分离培养大鼠HSC,采用Fura-2/AM钙荧光指示剂测定HSC细胞内Ca2+浓度,并观察ET-1对其影响。结果:ET-1在很短时间内即可明显提高HSC细胞内Ca2+浓度(P<0.01)。并且在无细胞外液Ca2+情况下,亦可提高[Ca2+]i,有明显的量效关系(P<0.05,P<0.01)。同时,维拉帕米对ET-1的上述作用具有显著的抑制作用(P<0.05)。结论:ET-1的促肝纤维化作用可能是通过[Ca2+]i运转而产生的。  相似文献   

5.
 In myometrial smooth muscle cells the rate of decline of intracellular calcium ([Ca2+]i) is determined by Ca2+ extrusion from the cell and uptake into intracellular stores. The relative quantitative contribution of these processes however, has not been established. We therefore examined the effect of the sarcolemmal Ca2+ pump inhibitor, carboxyeosin, on the rate of the [Ca2+]i transient decline in myocytes isolated from pregnant rat uterus. Indo-1 was used in conjunction with the whole-cell patch-clamp technique to measure [Ca2+]i simultaneously with transmembrane calcium current (I Ca). [Ca2+]i transients were elicited by repetitive membrane depolarization to simulate the natural pattern of uterine electrical activity. The rate of [Ca2+]i removal was calculated from the falling phase of the [Ca2+]i transient. Pre-treatment of the cells with 2 μM carboxyeosin led to a marked decrease in the rate of [Ca2+]i transient decay, suggesting that the sarcolemmal Ca2+ pump is involved in the calcium extrusion process. Removal of the extracellular Na also decreased the rate of [Ca2+]i decay, indicating an important role for the Na+/Ca2+ exchange. When both the sarcolemmal Ca2+ pump and Na+/Ca2+ exchange were inhibited the cell failed to restore [Ca2+]i after the stimulation. Comparison of the rate constants of [Ca2+]i decay in control conditions and after carboxyeosin treatment shows that approximately 30% of [Ca2+]i decay is due to the sarcolemmal calcium pump activity. The remaining 70% can be attributed to the activity of Na+/Ca2+ exchanger and the intracellular calcium stores. Received: 17 July 1998 / Received after revision: 23 September 1998 / Accepted: 25 September 1998  相似文献   

6.
目的:研究蕨类植物半边旗提取物6F对HL-60细胞内游离钙浓度([Ca2+]i)及Bcl-2蛋白表达的影响, Ca2+与6F细胞毒作用及诱导细胞DNA片段化的关系。方法:用荧光探针Fura-2/AM标记细胞内游离Ca2+, 在荧光分光光度计上测[Ca2+]i;流式细胞仪检测Bcl-2的表达;噻唑蓝(MTT)法测定细胞成活率;二苯胺法测DNA片段化形成率。结果:6F作用后, HL-60细胞内[Ca2+]i显著升高, 呈明显的时间剂量效应关系;6F降低Bcl-2的表达;于培养基中加2mmol/LCa2+、或加1mmol/LEDTA络合细胞外钙, 或加4μmol/L钙通道A23187升高细胞内钙浓度, 均可增强6F的细胞毒作用, 但均不影响6F诱导细胞DNA片段化程度。加入250μmol/LZn2+可显著降低6F所致DNA片段化率, 并可增强6F的细胞毒作用。结论:化合物6F可显著升高HL-60细胞[Ca2+]i, 推测与6F降低Bcl-2的表达有关;6F诱导HL-60细胞DNA片段化可能是通过Ca2+-非依赖性DNA酶的作用所致。  相似文献   

7.
目的:观察丹参在常氧和缺氧/复氧过程中对心肌细胞收缩和电刺激诱导的细胞内钙([Ca2+]i)瞬态的影响。方法: 采用酶解分离成年大鼠心室肌细胞化学缺氧模型, 用视频跟踪计算机系统和细胞内双波长钙荧光系统分别观察心肌细胞收缩力学和[Ca2+]i等指标。结果:丹参(1-9 g/L)处理后降低心肌细胞最大收缩和舒张速率、收缩幅度以及电刺激诱导的[Ca2+]i幅度, 且呈剂量依赖性。缺氧后, 与对照相比细胞收缩力和钙瞬态幅度降低、舒张末细胞长度缩短、舒张末钙水平增高;复氧后细胞收缩力、钙瞬态幅度和舒张末钙水平有所回复, 但不能达对照水平。用3 g/L的丹参处理后, 缺氧/复氧引起的心肌细胞最大收缩和舒张速率、收缩幅度和电刺激诱导的[Ca2+]i幅度高于单纯缺氧组, 舒张末[Ca2+]i水平低于单纯缺氧组。结论:丹参可对抗缺氧/复氧引起的大鼠心室肌细胞收缩力降低和细胞内动态和静态钙的变化。  相似文献   

8.
目的:观察脂多糖对大鼠肺微血管内皮细胞(RPMVECs)[Ca2+]i和Gq蛋白的影响及山莨菪碱的干预作用。方法:分离、培养并鉴定Wistar大鼠RPMVECs;应用Fura-2/AM法测定RPMVECs[Ca2+]i;流式细胞仪技术测定RPMVECsGq蛋白。结果:①LPS作用于RPMVECs30min和90min后,[Ca2+]i显著高于对照组;Gq蛋白显著低于对照组。②山莨菪碱可抑制LPS的上述作用。结论:①LPS致RPMVECs[Ca2+]i增加和Gq蛋白下降;②山莨菪碱通过抑制LPS诱导RPMVECs[Ca2+]i增加和Gq蛋白下降的作用而保护其内皮屏障功能。  相似文献   

9.
目的:慢性低氧时,心脏对β-肾上腺素受体激动的反应出现脱敏现象,细胞内钙[Ca2+]i瞬变的幅度降低、时程延长,本研究观察上述变化在低氧时发生和发展的时间过程和对应关系。方法:在年龄对等的正常及慢性低氧1d、3d、1周、2周、3周、4周和8周的大鼠,分别分离正常及慢性低氧条件下的心室肌细胞,以Fura-2为[Ca2+]i的指示剂,用光谱荧光法测定心肌细胞的[Ca2+]i瞬变及其对心肌β-受体激动后反应的变化。结果:在低氧1d、3d、1周等时间内,电刺激引起的[Ca2+]i瞬变、咖啡因引起的[Ca2+]i瞬变及电刺激引起的[Ca2+]i瞬变对β-受体激动剂异丙肾上腺素的增加反应无明显变化;在低氧2周以上时,电刺激引起的[Ca2+]i瞬变的幅度开始降低,而时程开始延长,其对异丙肾上腺素的反应也开始降低。咖啡因引起的[Ca2+]i瞬变幅度也开始降低;在低氧3周和4周时,上述变化程度逐渐加重;在低氧8周时各参数的变化有所恢复,但与4周时的变化程度无明显差异。结论:低氧2-4周时,心脏的β-肾上腺素受体发生脱敏现象,脱敏的机制与3种调节[Ca2+]i瞬变的蛋白质:L-型钙通道、ryanodine受体操纵的钙通道和钙泵等活性的降低有关,后者也可能是低氧时心脏功能降低的重要机制。低氧4-8周时,心脏对低氧产生了适应和代偿。  相似文献   

10.
目的:探讨三磷酸腺苷(ATP)敏感钾通道开放剂拉马克啉(Lev)对缺氧条件下培养的肺动脉内皮(PAEC)及平滑肌细胞(PASMC)的影响及其可能的作用机制。方法:分析Lev对缺氧条件下培养的PAEC及PASMC的[Ca2+]i、上清液中NO-2及ET-1水平、细胞内PKCα、eNOS、iNOS及PDGF-B的mRNA和蛋白质水平及PASMC增殖和凋亡的影响及其作用的细胞内机制。结果:①Lev可降低缺氧时PASMC及PAEC上清液中ET-1及细胞内PKCα、iNOS及PDGF-B的mRNA和蛋白质水平,可降低PASMC[Ca2+]i,抑制PASMC增殖,促其凋亡(P均<0.05),而对PAEC[Ca2+]i及PASMC、PAEC上清液中NO-2水平及细胞内eNOS的mRNA和蛋白质水平无明显影响(P均>0.05)。②Lev下调缺氧时PASMC及PAEC上清液中ET-1水平及PASMC增殖的机制涉及抑制缺氧时PKCα信号通道的功能活性。结论:Lev可减轻缺氧对PAEC及PASMC的某些不利影响,其作用的部分机制涉及下调缺氧时PAEC及PASMC内PKCα信号通道的功能活性和降低PASMC的[Ca2+]i,而与eNOS-NO信号通道无关。  相似文献   

11.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

12.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

13.
There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.  相似文献   

14.
Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.  相似文献   

15.
《Human immunology》2022,83(11):739-740
Georgia (or Sakartvelo in its own language) is a South Caucasus Mts. country with its easternmost part is enigmatically named Iberia, like the Iberian Peninsula, which may refer to rivers “Kura” and “Ebro” or their valleys respectively. Most of their inhabitants speak Georgian which is included within Dene-Caucasian group and Usko-Mediterranean subgroup of languages. The latter includes Basque, Berber, ancient Iberian-Tartessian, Etruscan, Hittite, Minoan Lineal A and others. In the present paper, HLA class II -DRB1 and -DQB1 alleles has been studied and extended haplotypes calculated. Most frequent haplotypes are also of Mediterranean origin (i. e.: (A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*51)-DRB1*13:01-DQB1*06:03, or (A*24-B*35)-DRB1*01:01-DQB1*05:01) and DA genetic distances show that closest world populations to Georgians are Mediterraneans. Georgians also show common extended haplotypes ((A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*13)-DRB1*07:01-DQB1*02:01 and (A*03-B*35)-DRB1*11:01-DQB1*03:01) with Svan people, a secluded population in North Georgia mountains. We can conclude that Georgians belong to a very old Mediterranean substratum according to both linguistics (Usko Mediterranean languages) and HLA genetics.  相似文献   

16.
Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.  相似文献   

17.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

18.
Introduction: The etiology of atopic dermatitis (AD) is multifactorial with interaction between genetics, immune and environmental factors.

Areas covered: We review the role of prenatal exposures, irritants and pruritogens, pathogens, climate factors, including temperature, humidity, ultraviolet radiation, outdoor and indoor air pollutants, tobacco smoke exposure, water hardness, urban vs. rural living, diet, breastfeeding, probiotics and prebiotics on AD.

Expert commentary: The increased global prevalence of AD cannot be attributed to genetics alone, suggesting that evolving environmental exposures may trigger and/or flare disease in predisposed individuals. There is a complex interplay between different environmental factors, including individual use of personal care products and exposure to climate, pollution, food and other exogenous factors. Understanding these complex risk factors is crucial to developing targeted interventions to prevent the disease in millions. Moreover, patients require counseling on optimal regimens for minimization of exposure to irritants and pruritogens and other harmful exposures.  相似文献   


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Fertility α2-microglobulin is one of the main proteins expressed between the late lutein phase of the menstrual cycle and the first gestation trimester. It is produced by endometrial secretory glandular epithelium and decidual membrane. It is believed to be involved in the preparation to gestation, conception, normal development of the fetoplacental system, and initiation of labor. The immunomodulating, effect of fertility α2-microglobulin and its possible involvement in the regulation of fertilization by blocking the spermatozoon reaction with the ovocyte lucid membrane were demonstratedin vitro. The data of structural analysis (appurtenance to lipocalines and unique pattern of N-glycosylation) and analysis of the spatial and temporal parameters of the expression in connection with other events in the organism within the same system of coordinates propated us to investigate the probability of realization of other, so far unknown functions of α2-microglobulin. The probable mechanisms of realization of the immunomodulating function are analyzed. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 10, pp. 364–373, October 1998  相似文献   

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